Ishibiki Formation, Chikanaga area: Coniacian, Japan

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Echinoidea - Spatangoida - Hemiasteridae
Bivalvia - Myalinida - Inoceramidae
see common names

Geography
Country:Japan
Coordinates: 33.3° North, 132.8° East (view map)
Paleocoordinates:39.6° North, 133.8° East (Wright 2013)
Geographic resolution:local area
Time
Period: Cretaceous Epoch: Late Cretaceous
Stage: Coniacian 10 m.y. bin: Cretaceous 6
Key time interval: Coniacian
Age range of interval: 89.8 - 85.7 m.y. ago
Stratigraphy
Geological group:Shimanto Formation:Ishibiki
Stratigraphic resolution:formation
Stratigraphy comments: STRATIGRAPHIC RELATIONS: From the Ishibiki Fm (Coniacian) of the lower Shimanto Group and Shimanto Supergroup, overlying the Furushiroyama Fm (Coniacian) and overlain by the Yorimatsu Fm (Santonian). AGE: Coniacian. STRATIGRAPHIC POSITION: List not specified to any part of the formation.
Lithology and environment
Primary lithology: "siliciclastic"
Includes fossils?Y
Lithology description: SPECIFIC LITHOLOGY: Lithology, unknown, presumably siliciclastic. LITHIFICATION: No evidence for lithification.
Environment:offshore
Geology comments: STRATIGRAPHY and STRUCTURE: The Shimanto Supergroup is a thick clastic sequence with minor basic volcanic rocks, chert and limestone. The Aptian, Albian, Turonian, and Conacian to Santonian strata are in fault contact with one another. The Lower Cretaceous, except for the Lower Aptian is regarded as rather deep offshore deposits, while the Upper Cretaceous as neritic, shelf deposits.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:field collection
Reason for describing collection:general faunal/floral analysis
Collection method comments: COLLECTOR: Collector unknown. REPOSITORY: Repository unknown.
Taxonomic list comments:COVERAGE: Suspected to only include biostratigraphically important taxonomic groups (i.e. inoceramids and ammonoids). NOMENCLATURE: Not an authoritative publication, but using subgeneric and species-level designations.
Metadata
Database number:65024
Authorizer:A. Hendy Enterer:A. Hendy
Research group:marine invertebrate
Created:2006-09-18 09:03:31 Last modified:2025-02-22 15:12:02
Access level:the public Released:2006-09-18 09:03:30
Creative Commons license:CC0
Reference information

Primary reference:
18725.1% 11980Y. Teraoka, I. Obata, and I. Mizuno. 1980. Stratigraphy of the Shimanto Supergroup in the Chikanaga area, west Shikoku, with special reference to the Miyakoan and Gyliakian Series. Bulletin of the Geological Survey of Japan 31(7):307-319 [A. Hendy/A. Hendy]